{ "id": "0904.3350", "version": "v3", "published": "2009-04-21T21:35:19.000Z", "updated": "2012-03-28T20:47:43.000Z", "title": "Newton-Okounkov bodies, semigroups of integral points, graded algebras and intersection theory", "authors": [ "Kiumars Kaveh", "A. G. Khovanskii" ], "comment": "39 pages. Revised in several places and the title slightly modified. Final version, to appear in Annals of Mathematics", "categories": [ "math.AG", "math.AC", "math.CO" ], "abstract": "Generalizing the notion of Newton polytope, we define the Newton-Okounkov body, respectively, for semigroups of integral points, graded algebras, and linear series on varieties. We prove that any semigroup in the lattice Z^n is asymptotically approximated by the semigroup of all the points in a sublattice and lying in a convex cone. Applying this we obtain several results: we show that for a large class of graded algebras, the Hilbert functions have polynomial growth and their growth coefficients satisfy a Brunn-Minkowski type inequality. We prove analogues of Fujita approximation theorem for semigroups of integral points and graded algebras, which imply a generalization of this theorem for arbitrary linear series. Applications to intersection theory include a far-reaching generalization of the Kushnirenko theorem (from Newton polytope theory) and a new version of the Hodge inequality. We also give elementary proofs of the Alexandrov-Fenchel inequality in convex geometry and its analogue in algebraic geometry.", "revisions": [ { "version": "v3", "updated": "2012-03-28T20:47:43.000Z" } ], "analyses": { "subjects": [ "14C20", "13D40", "52A39" ], "keywords": [ "graded algebras", "integral points", "intersection theory", "newton-okounkov body", "newton polytope theory" ], "note": { "typesetting": "TeX", "pages": 39, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009arXiv0904.3350K" } } }